Re: [PATCH] pgbench --throttle (submission 7 - with lag measurement)

> On 7/17/13 9:16 PM, Tatsuo Ishii wrote:
>> Now suppose we have 3 transactions and each has following values:
>>
>> d(0) = 10
>> d(1) = 20
>> d(2) = 30
>>
>> t(0) = 100
>> t(1) = 110
>> t(2) = 120
>>
>> That says pgbench expects the duration 10 for each
>> transaction. Actually, the first transaction runs slowly for some
>> reason and the lag = 100 - 10 = 90. However, tx(1) and tx(2) are
>> finished on schedule because they spend only 10 (110-10 = 10, 120-110
>> = 10). So the expected average lag would be 90/3 = 30.
>
> The clients are not serialized here in any significant way, even when
> they shared a single process/thread. I did many rounds of tracing
> through this code with timestamps on each line, and the sequence of
> events here will look like this:

My example is for 1 client case. So concurrent clients are not the
issue here.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
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